evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

sg_write()/bsg_write() is not fit to be called under KERNEL_DS

Browse source 
commit 128394eff343fc6d2f32172f03e24829539c5835 upstream.

Both damn things interpret userland pointers embedded into the payload;
worse, they are actually traversing those.  Leaving aside the bad
API design, this is very much _not_ safe to call with KERNEL_DS.
Bail out early if that happens.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Al Viro 2016-12-16 13:42:06 -05:00 • committed by Greg Kroah-Hartman
parent 7fb5a93645
commit d857273658
2 changed files with 6 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
block/bsg.c
View file

@ -655,6 +655,9 @@ bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
dprintk("%s: write %Zd bytes\n", bd->name, count);
if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
return -EINVAL;
bsg_set_block(bd, file);
bytes_written = 0;

3
drivers/scsi/sg.c
View file

@ -592,6 +592,9 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
sg_io_hdr_t *hp;
unsigned char cmnd[SG_MAX_CDB_SIZE];
if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
return -EINVAL;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,